Voice-based user interfaces or voice user interfaces (VUIs) are integral to systems, such as interactive voice response (IVR) systems, which are configured to enable speech-based interactions between machines and users. A VUI is designed by anticipating questions that users may ask during interactions and constructing a dialog with prompts to enable the users to receive assistance without the need to interact with a human agent. In conventional approaches, VUIs are designed based on business logic and designer intuition. However, designing VUIs in such a manner has several limitations. For example, designing VUIs in an unambiguous manner is often a cumbersome activity with limited rate of success when using conventional approaches. Further, designing VUIs capable of handling applications involving dialogs with a large number of prompts is often a challenge when using conventional approaches. Moreover, conventionally designed VUIs are rendered inflexible while handling natural language utterances (for example, normal speech conversations).